How to split a list into equal chuncks of a minimum size each?

Question

This will append 0, 1, 2 then 3, 4, 5 then 6, 7, 8. While I need it to append 0, 1, 2 then 3, 4, 5 then 6, 7, 8, 9. I need it to consider the whole contents of the list into the last group. Is that possible (knowing that I will consider those numbers for further operations)?

lst = [0,1,2,3,4,5,6,7,8,9]
templist=[]
ctr1=0
for i in range (int (len(lst)/3)):
  for n in lst[ctr1:3+ ctr1]:
    templist.append(n)
  ctr1+=3

print (templist)

Does this answer your question? [How do you split a list into evenly sized chunks?](https://stackoverflow.com/questions/312443/how-do-you-split-a-list-into-evenly-sized-chunks) — Arvind, Sep 29 '21 at 19:53

extDependency · Answer 1 · 2021-09-30T15:18:53.190

It's not clear to me exactly what you're trying to accomplish, so maybe this won't help you, but you can just add a check outside the for loop to see if there are remaining items in list:

lst = [0,1,2,3,4,5,6,7,8,9]
templist=[]
ctr1=0
for i in range (int (len(lst)/3)):
  for n in lst[ctr1:3+ ctr1]:
    templist.append(n)
  ctr1+=3
if len(lst) % 3:
    templist.extend(lst[ctr1:])


print (templist)

But you say you want equal chunks of a minimum size, but isn't that 2 instead of 3? Or do you mean the minimum number of chunks that are of an equal size? That would be 4.

Explanation of code: The modulo operator (%) returns the remainder of a division operation. So len(lst) % 3 basically does 10/3 and only gives us the remainder (in this case, 1). The entire statement if len(lst) % 3 basically say "if there is anything left over, as a remainder, of dividing 10 into three chunks. lst[ctr1:] In this part of the code, we know that ctr1 holds the value of the last item in the group of three (9 in this case), because that was the last increment in the for loop. So we can use ctr1 and slicing to grab everything from where ctr1 left off to the end of the list. I used extend rather than append because append would give us a sub-list in the list, but the rest of your code is just returning a list and I assumed you wanted the structure to match. If you wanted the remaining items as a sub-list of your templist, just change extend to append.

I mean the minimum size of a chunck is 3, however it can be bigger as in the last chunck. Thanks for your answer though!! — Riham ELSAADANY, Sep 29 '21 at 21:10
Would you kindly incorporate it properly within my code ? I tried but I don't see where I should include that check. Thanks in advance. — Riham ELSAADANY, Sep 30 '21 at 13:46
Sure, I've updated the code in my answer. It goes outside of the for loop (so it should be at the same top-level of indentation as `lst`, `templist`, `ctr1`, and the `for` loop header. And since it is checking for what is left in the list it goes after the `for` loop has completed. — extDependency, Sep 30 '21 at 15:10

score 0 · Answer 2 · answered Sep 30 '21 at 14:40

0

lst = [0,1,2,3,4,5,6,7,8,9]
templist=[]
ctr1=0
x = len(lst)
print ("x",x)
for i in range (int (len(lst)/3)):
    for n in lst[ctr1:3+ ctr1]:
        print ("hello")
        templist.append(n)
    #print (templist)
    print (x)
    y= x-3
    print ("y",y)
    if y<3 and y % 3: 
        templist.extend(lst[ctr1:])
        print ("yes")
    print (templist)
    #for n in lst[ctr1:3+ ctr1]:
        #templist.append(n)
    ctr1+=3
    x=x-3
print (templist)

answered Sep 30 '21 at 14:40

Riham ELSAADANY

61
4

Having run your code, I really can't see how it addresses the question at all. You should consider adding some explanation as to how this solves the OP's problem. – Adrian Mole Sep 30 '21 at 15:14

score -1 · Answer 3 · answered Sep 29 '21 at 21:08

-1

lst = [0,1,2,3,4,5,6,7,8,9]
templist=[]
ctr1=0
v = int (len(lst)/3)
for i in range (v):
  if i!= v-1:
    for n in lst[ctr1:3+ ctr1]:
      templist.append(n)
  if i==v -1:
    for n in lst[ctr1:]:
      templist.append(n)
  print (templist)
  ctr1+=3

answered Sep 29 '21 at 21:08

Riham ELSAADANY

61
4

While this code may answer the question, providing additional context regarding how and/or why it solves the problem would improve the answer's long-term value. You can find more information on how to write good answers in the help center: https://stackoverflow.com/help/how-to-answer . Good luck – nima Sep 30 '21 at 07:01

How to split a list into equal chuncks of a minimum size each?

3 Answers3